To make traveling with a motor vehicle easier and to prevent collisions with a car or other objects in the way so as to protect the occupants, sensors may be placed on the front and/or rear of the motor vehicle, the sensors emitting signals in order to receive the signals reflected by the obstacle. The distance between the sensor located on the motor vehicle and the obstacle may be determined from the time it takes the signal to travel from the sensor to the obstacle and back again. To register the objects, in particular to measure the distance, a variety of devices may operate on the basis of, for example, radar, lasers or ultrasound. Ultrasound sensors may come into play in particular at close range, because of their high resolution.
A device for registering objects, in particular as a parking assistance device in a motor-vehicle, is described in German Published Patent Application No. 199 01 847. Here all of the distance sensors are connected to a single microcontroller and an output unit.
Where all sensors are connected to a common controller, it may be undesirable that the controller be required to be configured for maximum possible capacity in order to allow future upgrading, even if only some areas of the vehicle are equipped with sensors at the moment. Thus, for customer-oriented equipping of the motor vehicle with sensors only in certain areas, the use of a universal, maximally configured controller may be expensive and technically complicated.
Furthermore, such a system may not be equipped for functional expansion with sophisticated algorithms and functions.